change response to OK for health check (#46)

Author: JannikStreek

backend/src/httpHandler.test.ts

@@ -8,6 +8,7 @@ import {
   handleGetImageRequest,
   handleUploadImageRequest,
   handleGetOwnDocumentsRequest,
+  handleHealthRequest,
 } from "./httpHandler";
 import { Document } from "../generated/prisma/client";
 import { downloadEncryptedImage } from "./utils/uploaderDownloader";
@@ -44,6 +45,15 @@ vi.mock("formidable", () => ({
   },
 }));
 
+describe("handleHealthRequest", () => {
+  it("responds with OK to health check", () => {
+    const response = mock<ServerResponse<IncomingMessage>>();
+    handleHealthRequest(response);
+    const result = response.end.mock.calls[0][0] as string;
+    expect(result).toEqual("OK");
+  });
+});
+
 describe("handleCreateDocumentRequest", () => {
   it("creates a document without owner", async () => {
     const doc = buildFullDocument({ ownerExternalId: null });

backend/src/httpHandler.ts

@@ -18,6 +18,13 @@ import { deleteImageFromBucket } from "./utils/s3";
 
 const DEFAULT_MAX_IMAGE_SIZE_BYTES = 1 * 1024 * 1024; // 1 MB default
 
+export const handleHealthRequest = (
+  response: ServerResponse<IncomingMessage>,
+): void => {
+  response.writeHead(200, { "Content-Type": "text/plain" });
+  response.end("OK");
+};
+
 export const handleCreateDocumentRequest = async (
   response: ServerResponse<IncomingMessage>,
   prisma: PrismaClient,
@@ -107,12 +114,11 @@ export const handleUploadImageRequest = async (
       }
     }
   } catch (error) {
-    if (
-      error instanceof Error &&
-      error.message.includes("maxTotalFileSize")
-    ) {
+    if (error instanceof Error && error.message.includes("maxTotalFileSize")) {
       response.writeHead(413, { "Content-Type": "text/json" });
-      response.end(JSON.stringify({ error: "File size exceeds maximum allowed size" }));
+      response.end(
+        JSON.stringify({ error: "File size exceeds maximum allowed size" }),
+      );
       return;
     }
     console.error(error);

backend/src/httpRouter.test.ts

@@ -9,11 +9,22 @@ import {
   handleGetImageRequest,
   handleUploadImageRequest,
   handleGetOwnDocumentsRequest,
+  handleHealthRequest,
 } from "./httpHandler";
 
 vi.mock("./httpHandler");
 
 describe("httpRouter", () => {
+  it("responds with OK to health check", async () => {
+    const payload = mock<onRequestPayload>();
+    payload.request.method = "GET";
+    payload.request.url = "/";
+    payload.request.headers = {};
+
+    await expect(httpRouter(payload, null)).rejects.toThrow();
+    expect(handleHealthRequest).toHaveBeenCalled();
+  });
+
   it("posts documents", async () => {
     const payload = mock<onRequestPayload>();
     payload.request.method = "POST";

backend/src/httpRouter.ts

@@ -5,6 +5,7 @@ import {
   handleGetImageRequest,
   handleUploadImageRequest,
   handleGetOwnDocumentsRequest,
+  handleHealthRequest,
 } from "./httpHandler";
 import { PrismaClient } from "../generated/prisma/client";
 import { onRequestPayload } from "@hocuspocus/server";
@@ -25,6 +26,13 @@ const httpRouter = async (data: onRequestPayload, prisma: PrismaClient) => {
   const modificationSecret = request.headers.authorization;
   const personId = extractPersonIdFromCookies(request.headers.cookie);
 
+  // health check response
+  if (method === "GET" && !resource) {
+    handleHealthRequest(response);
+    // eslint-disable-next-line @typescript-eslint/prefer-promise-reject-errors
+    return Promise.reject();
+  }
+
   if (method === "POST" && resource === "documents" && !subResource) {
     await handleCreateDocumentRequest(response, prisma, personId);
     // eslint-disable-next-line @typescript-eslint/prefer-promise-reject-errors